"There is much to be said for [Prandelli’s] musical sensitivity, fine phrasing, some lovely pianissimo singing, and attention to the text. His slightly nasal, bright, forward voice is ideal for the repertoire where he excelled – the basic romantic, mainly Italian operas."

- Charles H. Parsons, AMERICAN RECORD GUIDE, July/Aug., 2007

"Di Giulio was something of a holy grail….she was (evidently) one of those rare Latin sopranos of a certain type that sang the heaviest repertoire, now almost totally extinct….Di Giulio was a stunning woman physically, dark, voluptuous and sensual….But that voice! I'd say she was a Latin equivalent of Varnay. The fullness within the entire range is remarkable: the middle had a solid depth to its core that indicates her voice was quite sizable. The lows are astounding….the top is a bit like Varnay's too; a bit disconnected from the rest, the kind one would have freely in youth, but which would be a challenge when one got older. It's one of those voices, by nature, where you could guess the vocal cords are really thick, and big. Most of these big dramatic sopranos have that typically physical, vocal and facial physiologies - wide faces, huge palates, and not delicate looking. Di Giulio's voice is in some respects an earlier Cerquetti. Di Giulio pays enough attention to the line, but she was one of those singers who threw herself into the drama of the music more than anything else….Gioconda's desperation is made implicit….Di Giulio is all what you'd think of as rustic Sicilian overwroughtness - and her Santuzza must have been a powerful experience….[Her ‘Pace, pace mio Dio!’] isn't Tebaldi or Milanov, but it is more emotional, desperate, more text-punctuated. The piano B-flat 'Invan la pace' she astonishes with a very clearly made messa-di-voce; it's quite vibrant in tonal quality, but - it is an amazing feat….The TOSCA duets with Giacinto Prandelli are typical of that time: two healthy Italian voices completely at home in this music.”